As the Supreme Court begins its 2012 term Monday, two cases loom ominously large for civil rights advocates.

As the Supreme Court begins its 2012 term Monday, two cases loom ominously large for civil rights advocates who fear that the Roberts court is itching to prematurely declare victory in the long legal war against racial discrimination. One, which the court is expected to accept for review although it hasn't done so yet, involves a key provision of the 1965 Voting Rights Act. The other concerns a program at the University of Texas that allows race to be considered in admissions decisions.

Like the challenge to the constitutionality of President Obama's healthcare law, these cases will test the commitment of the court's conservatives, and Chief Justice John G. Roberts Jr. in particular, to judicial restraint.

Legal conservatives abhorred "Obamacare," and they are equally critical of both affirmative action and the Voting Rights Act's requirement that states with a history of racial discrimination in voting "pre-clear" their election procedures with the Justice Department or a federal court in Washington. Such extraordinary measures to protect African Americans and other minorities may have been necessary in the past, the argument goes, but racial progress (symbolized for some by the election four years ago of a black president) requires an end to such initiatives and a reaffirmation of the ideal of a "colorblind" Constitution.

We don't agree with the notion that race-conscious remedies for discrimination are no longer needed. But in any case, that's not the issue the court needs to decide; it merely needs to determine whether they are prohibited by the Constitution.

In the voting rights case, Shelby County in Alabama is challenging the pre-clearance provisions of Section 5 of the Voting Rights Act, which requires advance approval of any voting-related change, no matter how minor, in parts or all of 16 states, many of which are Deep South states with long histories of discrimination. In asking that Section 5 be declared unconstitutional, Shelby County relies on familiar arguments, including the contention that minorities vote and are elected to office in pre-clearance states at rates comparable to those in other states.

Several justices may be sympathetic to those arguments. In 2009, Roberts noted that "things have changed in the South" and therefore that Section 5 and the formula used to trigger pre-clearance raised "serious constitutional questions." But Congress spent a good deal of time studying the issue when it extended Section 5 in 2006 and concluded that voting discrimination requires special attention in so-called covered jurisdictions. That congressional judgment is entitled to deference from the Supreme Court.

In the affirmative action case, the court will be reviewing decisions of the University of Texas, not Congress. But here too restraint is in order.

In 2003, in a case involving the University of Michigan Law School, the court ruled that state universities could use race as one factor in assessing applicants. Relying on that decision, the University of Texas decided to consider race in allotting places in the freshman class. It had previously been using another system to encourage diversity in which it automatically accepted all students who had finished in the top 10% of their high school classes. But it added the new race-conscious policy partly because the top-10 approach didn't benefit talented minority students from competitive integrated high schools.

In the nine years since the University of Michigan decision, the arguments for and against the use of race in college admissions haven't changed. What has is the makeup of the Supreme Court. Justice Sandra Day O'Connor, who wrote the majority opinion in the Michigan case, has been replaced by Justice Samuel A. Alito Jr., who is regarded by opponents of affirmative action as a possible vote to reverse the 2003 ruling. Overturning a precedent — something Roberts described in his confirmation testimony as a "jolt to the legal system" — should only happen in rare cases involving grievous miscarriages of justice; it requires more justification than the fact that one justice has replaced another.

The court conceivably could strike down the University of Texas' use of race in admissions on the grounds that the top-10 plan already ensures a racially diverse student body. Or, as we would prefer, it could allow the University of Texas to pursue a policy similar to the one it upheld in the Michigan case. What it should not do, in this case or in the voting rights case, is upend settled law on the naive assumption that racism and racial discrimination are ancient history.